A composite material comprises an appropriate resin and one or more fiber reinforcements. The resin may be either thermoplastic or thermosetting, and the fibers may be of various different materials depending upon the properties desired for the resulting composite material. For example, the fibers may be of an electrically conductive material, such as graphite.
Composite materials can be provided in various different forms. The composite material comprises a matrix of an appropriate resin and reinforcing fibers. The composite material may be provided in sheet or tape form. In another form, the composite material comprises yarns that are coated with a powder of the matrix resin or fibers.
It is often necessary or desirable to process composite materials of this type utilizing heat and pressure. For example, it may be desirable to process the composite material utilizing a controlled thermal cycle to alter the properties of the resin. A tape or sheet of composite material can be processed to change the shape of the sheet. Finally, the composite material may be processed to bond together multiple tapes of sheets or multiple powder-coated yarns.
One kind of known apparatus for processing composite materials includes rigid blocks or rollers for providing pressure after the composite material has been heated. These rigid members cannot conform to different contours, nor can they provide as uniform a pressure as is desired. Heating of the composite material in these apparatuses is accomplished by conduction from a hot block, radiation from a light source or by superheated air. These heating techniques are limited as to the speed that heating can occur in that heat must be conducted into the composite material from the surface.